1. Field of the Invention
The present invention relates to a method of producing aerial photograph data and the data obtained by such method. In particular, the present invention relates to a method of producing aerial photograph data which enable novel utilizations of aerial photographs. The present invention also relates to aerial photograph data which can be utilized in various ways.
2. Description of the Related Art
Aerial photograph images have conventionally been utilized in various ways. For example, they are utilized in photogrammetry for topographic mapping production, industrial surveying, cultural property surveying, natural disaster surveying and so on. When utilized for such application, the aerial photograph images are sometimes produced as stereo images. The stereo images are obtained by generating pair links to assign a certain relationship to the aerial photograph images and searching the pair links. This method is described for example in Japanese Laid-Open Patent Publication Nos. 2001-28049, 2002-5659, 2003-32364, and 2006-018549. A special method of processing the aerial photograph images for easy observation is described in Japanese Laid-Open Patent Publication No. 2005-156514.
The aerial photography (aerophotography) for obtaining the aerial photograph image is typically conducted such that the photographic images partially overlap both lengthwise and crosswise at a endlap ratio and a sidelap ratio. Japanese Laid-Open Patent Publication No. 2005-156514 mentioned above also describes the utilization of such overlapping images.
The conventional methods described above however have various problems. For instance, it takes time to access desired images. A large amount of labor and time are also required to prepare the desired images. Furthermore, it is not easy to obtain the desired image. There is a demand for improvement for solving these problems. For example, when the overlapping of aerial photographs as described in Japanese Laid-Open Patent Publication No. 2005-156514 above is utilized to observe a desired place from a desired direction, it takes time to generate a required data set. When stereo images are to be obtained, pair links need be produced in advance, and then access is performed by using the pair link information. Therefore, considerable skill or time is required to perform such access.